The Atlanta area experiences a wide range of temperatures from season to season, with winter readings dropping below freezing and summer days that average around 90 degrees but can reach into the 100s. These extremes in temperature require the regular usage of the most energy intensive appliances in the typical home; the heating and cooling systems. In Atlanta, the costs of running these climate controls can exceed $2,000 per year in an un-insulated home, but these expenses can be reduced by 30 percent or more by installing the recommended amount of insulation and venting in the attic. Here are the measures that can save over $600 per year.
1) Insulation – Determine the optimal amount of insulation for your home – The Department of Energy sets the recommended amount of insulation for homes based on their geographic location, which is expressed as an R-Value. In Atlanta, as with most areas in the U.S., the minimum recommended R-Value for the attic is 30, with the highest level of energy efficiency being delivered by insulation with an R-Value of 60. These will be the baseline numbers for homes with no insulation. Many homes do have some insulation, but if the home was built prior to 1980 and no insulation has been added since, the typical R-Value will be under 15. According to the DoE, bringing the insulation up to recommended standards and sealing leaks in the living areas of a home can reduce heating and cooling bills by an average of 20 percent.
2) Ventilation – Ventilating and insulating the attic at the same time may seem counterintuitive, but each measure serves a different purpose. Insulation is meant to inhibit the transfer of heat into and out of the house. Ventilating the space regulates the temperatures inside the attic, which can still reach 150 degrees in an insulated home during hot summer days. Regulating the temperature in an attic provides two benefits; it reduces heat that might otherwise radiate into the living areas of the home and lowers the level of heat that radiates up to the roof deck and the roofing materials. The rule of thumb for adequate ventilation is that for every 300 square inches of floor space, there should 1 square inch of open ventilation. For example, an attic that measures 500 square feet would be multiplied by 12 to get 6,000 square inches. To calculate the amount of square inches for ventilation, 6,000 inches would be divided by 300 with the result being 20 square inches of ventilation. In this example, the 20 inches allocated for ventilation should be split between intake vents at the soffit and exhaust vents at the highest point in the attic to facilitate circulation.
While many home improvements don’t return much on the investment, the same is not true for adding insulation and ventilation to an attic. With savings that can range from $400 to $600 per year, the initial investment for insulation and ventilation will likely be returned many times over in the years that follow.
